1. Field of the Invention
The present invention relates to a vehicular upholstery fabric mainly composed of polypropyleneterephthalate fibers.
2. Description of the Invention
For preservation of the global environment, natural fibers such as cotton, linen, silk, wool, and the like are preferably used because these fibers do not depend on non-renewable petroleum resources.
In this regard, a polypropyleneterephthalate fiber, called “PPT-fiber”, and a polylacticacid fiber are synthetic fibers that can be produced from natural plant fibers rather than from petroleum.
Japanese Patent Laid Open No. 2000-154457, Japanese Patent Laid Open No. 2002-004156, Japanese Patent Laid Open No. 2003-105653, Japanese Patent Laid Open No. 2000-328393, Japanese Patent Laid Open No. 2005-113279, and Japanese Patent Laid Open No. HEI-11-093050, disclose PPT-fiber and polylacticacid fiber that can be used for a vehicular upholstery fabric.
Since the vehicular upholstery fabric is used under severe conditions, polyethyleneterephthalate fiber is mainly used for the vehicular upholstery fabric, as natural fibers and rayon are lacking in durability. Thus, natural fibers and rayon are not desirably used for vehicular upholstery fabric.
In this regard, PPT-fibers and polylacticacid fibers are relatively new materials used for the vehicular upholstery fabric, since the chemical formula of polypropyleneterephthalate, known as “PPT”, and polylacticacid are similar to the chemical formulas of polyethyleneterephthalate, known as “PET”. However, polylacticacid fiber lacks in corrosion resistance since it is a type of biodegradable fiber.
Further, polylacticacid fiber lacks in the ability to absorb dyes.
Therefore, in the case of application of the polylacticacid fiber for use as a vehicular upholstery fabric, it must be chemically treated.
In this regard, in comparison to PET-fiber, the Young's Modulus of PPT-fiber is lower, the rate of elastic recovery of PPT-fiber is higher, and PPT-fiber is rich in flexibility and stretching property.
Thus, it is expected that vehicular upholstery fabric having an agreeable texture will be obtained by using PPT-fiber rather than PET-fiber.
However, in comparison to PET-fiber, PPT-fiber has less than ideal heat setting properties during interlacing treatment. And, in comparison with PET-fiber, it is difficult to make the PPT-fiber fabric bulky during the raising treatment.
Further, in comparison with PET-fiber, PPT-fiber fabric easily shrinks when heated during the dyeing and finishing treatment.
Thus, heretofore it has been difficult to produce vehicular upholstery using PPT-fiber fabric.
The object of the present invention is to make PPT-fiber practical to use in the full scale production of vehicular upholstery, despite PPT-fiber having less ideal characteristics than PET-fiber.